Bolt Buffer and Firearm

ABSTRACT

Firearms and buffer systems having a second buffer spring or having a buffer spring and a buffer adjusting nut, for instance, to absorb recoil energy, reduce recoil forces, or both. In some embodiments, a first buffer spring is aft of the bolt assembly and a second buffer spring is forward of the first buffer spring, forward of the carrier assembly, or a combination thereof. In some embodiments, a buffer adjusting nut adjusts preload of the second buffer spring, contacts the second buffer spring, or both. In particular embodiments, a buffer weight is located between the first buffer spring and the carrier assembly or the second buffer spring, the first buffer spring is longer than the second buffer spring, the first buffer spring is less stiff than the second buffer spring, the first buffer spring and the second buffer spring have a common axis, or a combination thereof.

RELATED PATENT APPLICATIONS

This patent application claims priority to U.S. Provisional Patent Application No. 61/932,874, filed on Jan. 29, 2014, titled BOLT BUFFER AND FIREARM, which has at least one inventor in common with the current patent application and the same assignee. The contents of this priority provisional patent application are incorporated herein by reference. This patent application also claims priority, as a continuation-in-part patent application, to U.S. Non-Provisional patent application Ser. No. 14/593,116, filed on Jan. 9, 2015, titled CARRIER GUIDE AND FIREARM, which has at least one inventor in common with the current patent application and the same assignee. The contents of this priority non-provisional patent application are also incorporated herein by reference.

FIELD OF THE INVENTION

Various embodiments of this invention relate to firearms. Particular embodiments relate to firearms having bolt buffer springs that reduce recoil forces.

BACKGROUND OF THE INVENTION

Firearms have been used for several centuries for various purposes including as weapons for warfare, law enforcement, self defense, hunting, and target practice. Although many new weapons and weapon systems have been developed, firearms are still widely used and soldiers are trained in firearm use and carry firearms in essentially all armies throughout the world. Over time, firearms have been improved in many ways, but opportunities for improvement still exist in particular areas and for particular aspects of these devices.

Firearms have been constructed with a bolt assembly, a carrier assembly, and a main buffer spring. When such a firearm is discharged, the bolt assembly and the carrier assembly are propelled rearward by the products of combustion and compress the main buffer spring. The main buffer spring then pushes the bolt assembly and the carrier assembly forward, which loads another round from the magazine into the chamber for firing. In addition to loading the next round, the buffer spring absorbs some of the recoil from firing the weapon. Main buffer springs, however, typically have not absorbed all of the recoil of a firearm. If a main buffer spring is selected to be stiff enough to absorb all of the recoil, the buffer spring has been found to be too stiff to allow the operator to pull back the charging handle to charge the weapon. As a result, a significant portion of the recoil forces have been absorbed by the operator's shoulder, which has caused the operator discomfort, soreness, fatigue, and distraction, among other things. These effects can be particularly negative when the weapon is fired repeatedly, the operator is small or frail, the operator is already injured or sore, the operator is inexperienced, the operator does not hold the weapon properly, or the charge is particularly powerful.

Needs or potential for benefit or improvement exist for firearms wherein more of the recoil energy or force is absorbed by the firearm rather than by the operator, that are more comfortable to operate, particularly when fired repeatedly, that are smoother in operation, that operate with less shock, that are more robust, or a combination thereof, as examples. Room for improvement exists over the prior art in these and other areas that may be apparent to a person of skill in the art having studied this document.

SUMMARY OF PARTICULAR EMBODIMENTS OF THE INVENTION

This invention provides, among other things, firearms and buffer systems, for example, for absorbing the recoil energy of the weapon. Various embodiments provide firearms with an additional buffer spring, for example, aft of the bolt assembly or between the bolt assembly and the carrier assembly. Further, certain embodiments include a buffer adjusting nut, for example, that adjusts preload of at least one buffer spring. Various embodiments provide, for example, as an object or benefit, that they partially or fully address or satisfy one or more of the needs, potential areas for benefit, or opportunities for improvement described herein, or known in the art, as examples.

In a number of embodiments, more of the recoil energy is absorbed by the firearm rather than by the operator in comparison with certain prior art alternatives. Further, a number of embodiments are more comfortable to operate, particularly when fired repeatedly. Even further, certain embodiments are smoother in operation, operate with less shock, are more robust, are easier to operate, or a combination thereof, as examples. In a number of embodiments, improvements to firearms herein provide for firearms that are more reliable, that last longer, that are more adaptable, that can be used in conditions that are more extreme, that handle abuse well, that work better, that are easier to use, that are easier to maintain, that are less expensive to manufacture, that have a lower lifecycle cost, that offer more options for use, that can be fired more easily for a longer period of time, or a combination thereof, in comparison with certain alternatives.

Specific embodiments include various firearms that each include, for example, a bolt assembly, a first buffer spring, for instance, aft of the bolt assembly, and a second buffer spring, for example, between the bolt assembly and the first buffer spring. Further, some embodiments include a buffer adjusting nut, for instance, that adjusts preload of the second buffer spring. Even further, in some embodiments, the buffer adjusting nut is aft of the second buffer spring. Further still, in various embodiments, the first buffer spring and the second buffer spring have a common axis. Still further, in a number of embodiments, the first buffer spring is longer than the second buffer spring. Even further still, some embodiments include a buffer weight, for instance, located between the first buffer spring and the second buffer spring. In various embodiments, the second buffer spring acts to reduce peak recoil force produced by the firearm, the second buffer spring acts to absorb recoil energy produced by the firearm, or both.

Other specific embodiments include various firearms that include, for example, a bolt assembly, a carrier assembly, a first buffer spring, for instance, aft of the carrier assembly, and a second buffer spring, for example, between the bolt assembly and the carrier assembly. Further, some such embodiments include a buffer adjusting nut. In some embodiments, the buffer adjusting nut adjusts preload of the second buffer spring, contacts the second buffer spring, is aft of the second buffer spring, or a combination thereof, as examples. Still further, some embodiments include a buffer weight, for example, located between the first buffer spring and the carrier assembly. In a number of embodiments, the first buffer spring is longer than the second buffer spring, the first buffer spring and the second buffer spring have a common axis, or both. Moreover, in various such embodiments as well, the second buffer spring acts to reduce peak recoil force produced by the firearm, the second buffer spring acts to absorb recoil energy produced by the firearm, or both.

Still other specific embodiments include certain buffer systems for firearms, for example, each firearm including a bolt assembly and a carrier assembly. In a number of embodiments, for instance, a buffer system for a firearm includes a buffer spring and a buffer adjusting nut, and the buffer adjusting nut adjusts preload of the buffer spring. Certain embodiments further include a buffer weight, the buffer adjusting nut contacts the buffer spring, or both. In addition, various other embodiments of the invention are also described herein, and other benefits of certain embodiments may be apparent to a person of skill in this area of technology.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings provided herewith illustrate, among other things, examples of certain aspects of particular embodiments. Various embodiments may include aspects shown in the drawings, described in the specification (including the claims), known in the art, or a combination thereof, as examples. Other embodiments, however, may differ.

FIG. 1 is a right-side cross-sectional view of an embodiment of a firearm having an example of a buffer system; and

FIG. 2 is a detail right-side cross-sectional view of part of the firearm of FIG. 1 showing, among other things, the lower receiver, most of the upper receiver, the bolt assembly, the carrier assembly, and the buffer system, including the first buffer spring, the second buffer spring, and the buffer adjusting nut of this particular example.

DETAILED DESCRIPTION OF EXAMPLES OF EMBODIMENTS

This patent application describes, among other things, examples of certain embodiments, and certain aspects thereof. Other embodiments may differ from the particular examples described in detail herein. Various embodiments are or concern firearms, for example, having improvements over the prior art. Different embodiments include firearms, mechanisms for firearms, buffer systems, and methods concerning buffers and buffer systems for firearms, as examples.

Referring to FIGS. 1 and 2, in a number of embodiments, a firearm (e.g., 10) includes a bolt assembly (e.g., 28), a carrier assembly (e.g., 26), a first buffer spring (e.g., 21), for instance, aft of carrier assembly (e.g., 26), and a second buffer spring (e.g., 22), for example, between the bolt assembly (e.g., 28) and the carrier assembly (e.g., 26). As used herein, “aft” means the direction opposite the direction that the bullet is traveling in when the bullet leaves the firearm (e.g., 10), within 15 degrees. In contrast, as used herein, “forward” means the direction that the bullet is traveling in when the bullet leaves the firearm (e.g., 10), within 15 degrees. Further, as used herein, “aft” or “forward” when referring to the arrangement of parts, or other directions described herein, unless stated otherwise, refer to when the firearm is assembled and ready for firing.

In various embodiments, the carrier assembly (e.g., 26) is aft of the bolt assembly (e.g., 28). In some embodiments, however, part of the carrier assembly (e.g., 26) may overlap with part of the bolt assembly (e.g., 28), however. As used herein, a first component or assembly is considered to be aft of a second component or assembly if the center of mass of the first component or assembly is aft of the center of mass of the second component or assembly. Further, “forward” as used herein, has a similar but opposite meaning in comparison with “aft”.

Such a firearm (e.g., 10) can include other components or assemblies as well, which may be known in the art, such as a barrel (e.g., 13 shown in FIG. 1), chamber, firing pin, magazine, receiver (e.g., upper receiver 11 and lower receiver 12), stock, trigger, trigger mechanism, etc. The first buffer spring (e.g., 21) in a number of embodiments, is a main buffer spring, for example, and the second buffer spring (e.g., 22), in a number of embodiments, is a bolt buffer spring. Further, in many embodiments, the bolt assembly (e.g., 28) includes at least a bolt and the carrier assembly (e.g., 26) includes at least a carrier, but these assemblies can include other components as well. Thus, as used herein, an “assembly” can include one or more different components. In some embodiments, for example, the bolt assembly (e.g., 28) and the carrier assembly (e.g., 26) collectively form a bolt carrier group (e.g., 27).

In a number of embodiments, a firearm (e.g., 10) includes a sub-combination of the components or features described herein. For example, in some embodiments, a firearm (e.g., 10) includes a carrier assembly (e.g., 26), a first buffer spring (e.g., 21) aft of the carrier assembly (e.g., 26), and a second buffer spring (e.g., 22), for example, forward of the carrier assembly (e.g., 26). Further, in some embodiments, a firearm (e.g., 10) includes a bolt assembly (e.g., 28) a first buffer spring (e.g., 21), for example, aft of the bolt assembly (e.g., 28), and a second buffer spring (e.g., 22), for instance, between the bolt assembly (e.g., 28) and the first buffer spring (e.g., 21). Various embodiments include other combinations of the features described herein. All feasible combinations are contemplated.

Further, in certain embodiments, the first buffer spring (e.g., 21) is a helical spring, the second buffer spring (e.g., 22) is a helical spring, or both. Still further, in some embodiments, the first buffer spring (e.g., 21), the second buffer spring (e.g., 22), or both, are loaded in compression, for instance, when the firearm (e.g., 10) is fired, or in a number of embodiments, also when the firearm (e.g., 10) is assembled and ready for firing. Even further, some embodiments include a buffer adjusting nut (e.g., 29 shown in FIG. 2). Such a buffer adjusting nut (e.g., 29) adjusts preload of the second buffer spring (e.g., 22) in some embodiments, for instance, when turned by hand. In certain embodiments, for example, the buffer adjusting nut (e.g., 29) is adjusted when the firearm (e.g., 10) is partially disassembled, for instance, when the upper receiver (e.g., 11) is partially or fully separated from lower receiver (e.g., 12).

In particular embodiments, the buffer adjusting nut (e.g., 29) contacts the second buffer spring (e.g., 22). Further still, in particular embodiments, the buffer adjusting nut (e.g., 29) is aft of the second buffer spring (e.g., 22). In different embodiments, the buffer adjusting nut (e.g., 29) can be internally threaded or externally threaded, for instance, and can thread onto or into the bolt assembly (e.g., 28) or the carrier assembly (e.g., 26), as examples. Even further still, some embodiments include a buffer weight (e.g., 23), for instance, located between the first buffer spring (e.g., 21) and the carrier assembly (e.g., 26), between the first buffer spring (e.g., 21) and the second buffer spring (e.g., 22), or both. An example is shown.

In various embodiments, the first buffer spring (e.g., 21) is longer than the second buffer spring (e.g., 22), for instance, in the direction of the axis of the helix of the spring, or in a direction parallel to the barrel (e.g., 13) of the firearm (e.g., 10). As used herein, the length of a spring is determined when the spring is relaxed, for example, when the spring has been removed from the firearm. Further, in some embodiments, the first buffer spring (e.g., 21) is less stiff than the second buffer spring (e.g., 22). In a number of embodiments, for example, the second buffer spring (e.g., 22) is made of a larger diameter wire, is wound in a smaller diameter helix, has fewer coils or windings, or a combination thereof), or both, for instance, in comparison with the first buffer spring (e.g., 21). In other embodiments, however, the first buffer spring (e.g., 21) is stiffer than the second buffer spring (e.g., 22). Still further, in certain embodiments, the first buffer spring (e.g., 21) and the second buffer spring (e.g., 22) have a stiffness that is equal or substantially equal, as another example. As used herein, unless stated otherwise, “equal” means equal to within 5 percent, and “substantially equal” means equal to within 10 percent.

Further still, in a number of embodiments, the first buffer spring (e.g., 21) and the second buffer spring (e.g., 22) have a common axis (e.g., center of the helix). As used herein, two spring axes are considered to have a common axis if the axes of the two springs fall on the same line (i.e., when the firearm (e.g., 10) is assembled and ready for firing) to within ¼ inch over the length of the two springs. In other embodiments, the first buffer spring (e.g., 21) and the second buffer spring (e.g., 22) have a common axis to within ⅛, 3/16, 5/16. ⅜, or ½ inch, as other examples.

In a number of embodiments, the first buffer spring (e.g., 21), the second buffer spring (e.g., 22), or both, is a metal spring, for example, steel. In some embodiments, however, the first spring, the second spring, or both, is an air spring. Further, in some embodiments, the first spring, the second spring, or both, is dampened, for example, with a hydraulic or pneumatic damper, with dry friction, or a combination thereof, as examples. In some embodiments, the firearm (e.g., 10) or the upper receiver (e.g., 11) is configured with an appropriate tolerance, one or more seals, or both, so that when the bolt assembly (e.g., 28), carrier assembly (e.g., 26), or buffer weight (e.g., 23), (or a combination thereof) move after a round is fired, the bolt assembly (e.g., 28), carrier assembly (e.g., 26), or buffer weight (e.g., 23), (or a combination thereof) traps air that then compresses, flows through the tolerance or an orifice, or a combination thereof, as examples, to absorb recoil energy, dampen motion, or both.

Even further, in some embodiments, a bumper or bump stop, for example, made of rubber or an elastomeric material, can be used, for instance, in combination with or instead of a spring. Further, where embodiments are described herein that include a spring, other embodiments are contemplated wherein a rubber or elastomeric bump stop is substituted for or used in combination with the spring. A rubber or elastomeric bump stop, however, is not considered to be a “spring” as that term is used herein. Even further still, in some embodiments, as other examples, multiple springs can be used where a spring, such as the second buffer spring (e.g., 22), is described herein (e.g., 2, 3, or 4 concentric helical springs). Further, in some embodiments, the carrier assembly (e.g., 26) is heavier than the bolt assembly (e.g., 28).

Other embodiments, besides firearms (e.g., 10), include buffer systems (e.g., 20) for firearms (e.g., 10). Such a firearm (e.g., 10) can include a bolt assembly (e.g., 28), a carrier assembly (e.g., 26), or both, for example. Further, the buffer system (e.g., 20), in a number of embodiments, includes a first buffer spring (e.g., 21), for instance, aft of the carrier assembly (e.g., 26) a second buffer spring (e.g., 22), for example, between the bolt assembly (e.g., 28) and the carrier assembly (e.g., 26), or both. Such a buffer system (e.g., 20), or a firearm (e.g., 10) containing such a buffer system (e.g., 20), can further include, in particular embodiments, a combination (e.g., any combination or subcombination) of the features recited herein, or known in the art, for instance, for a firearm (e.g., 10).

In certain embodiments, for example, a buffer system (e.g., 20) includes a buffer spring (e.g., second buffer spring 22) and a buffer adjusting nut (e.g., 29), and the buffer adjusting nut (e.g., 29) adjusts preload of the buffer spring (e.g., second buffer spring 22). An example is illustrated. Some embodiments further include a buffer weight (e.g., 23). Further, in a number of embodiments, the buffer adjusting nut (e.g., 29) contacts the buffer spring (e.g., second buffer spring 22). Still further, certain embodiments further include an additional buffer spring (e.g., first buffer spring 21). Even further, particular embodiments of a buffer system (e.g., 20) include other components described herein (e.g., of firearm 10), perform particular functions described herein, or both.

Still other embodiments include certain methods that pertain to buffer systems (e.g., 20) for firearms (e.g., 10), firearms (e.g., 10), that include buffer systems (e.g., 20), or both. Particular methods can include acts of obtaining or providing, as examples, other features, components, or aspects described herein. All possible combinations are contemplated. Further, methods described herein contain various acts. The order in which these acts are described herein may be an example of the order in which these acts can be performed, but in other embodiments, unless stated otherwise herein or precluded by other factors, the acts may be performed in a different order. In some embodiments, acts may overlap or be performed at the same time, as another example.

Particular embodiments include certain methods of absorbing recoil energy of a firearm (e.g., 10), for instance. Such a method can include, for example, at least the acts of: obtaining or providing a first buffer spring (e.g., 21), obtaining or providing a second buffer spring (e.g., 22), or both. In some embodiments, the method further includes locating the first buffer spring (e.g., 21) aft of a carrier assembly (e.g., 26) of the firearm (e.g., 10). Further, in a number of embodiments, the method further includes locating the second buffer spring (e.g., 22) aft of a bolt assembly (e.g., 28) of the firearm (e.g., 10). Further still, in some embodiments, the method further includes locating the second buffer spring (e.g., 22) forward of a carrier assembly (e.g., 26) of the firearm (e.g., 10). Different embodiments include some or all of such acts.

Yet other embodiments include various methods of making a firearm (e.g., 10) easier to be used (e.g., at least by certain people). Such a method can include, for example, obtaining, providing, or manufacturing the firearm (e.g., 10) having a bolt assembly (e.g., 28), a carrier assembly (e.g., 26), a first buffer spring (e.g., 21), for instance, aft of the carrier assembly (e.g., 26), a second buffer spring (e.g., 22), for example, between the bolt assembly (e.g., 28) and the carrier assembly (e.g., 26), or a combination thereof. In different embodiments, a method (e.g., as described herein) further includes acts of obtaining or providing a combination of the components or features recited herein (e.g., above). Various methods can further include acts of manufacturing other components described herein, shown on the drawings, or both.

In various embodiments, when the firearm (e.g., 10) is fired, the trigger is pulled and the bullet is fired, and gas from the bullet discharge pushes, for example, the carrier assembly (e.g., 26) aft. As the carrier assembly (e.g., 26) moves aft, for instance, it engages, pushes on, or compresses (or a combination thereof) the bolt buffer spring or second buffer spring (e.g., 22). In a number of embodiments, this will diminish impact on the main buffer spring or first buffer spring (e.g., 21). Further, in various embodiments, this will, in turn, diminish the impact on the operator. In some embodiments, as the carrier assembly (e.g., 26) continues to move aft, for example, it engages the cam pin (e.g., 30), which is attached to the bolt assembly (e.g., 28). In a number of embodiments, the carrier assembly (e.g., 26) and bolt assembly (e.g., 28) continue moving aft, which engages, pushes on, or compresses (or a combination thereof) the main buffer or buffer weight (e.g., 23) and the main buffer spring or first buffer spring (e.g., 21), for example, at a reduced speed or acceleration (e.g., in comparison to an otherwise equivalent firearm without a second buffer spring, for instance, 22). In various embodiments, the main buffer spring or first buffer spring (e.g., 21) returns the carrier assembly (e.g., 26) and the bolt assembly (e.g., 28) forward.

In a number of embodiments of a firearm (e.g., 10), buffer system (e.g., 20), or method, as examples, the second buffer spring (e.g., 22) acts to reduce peak recoil force produced by the firearm (e.g., 10). Further, in some embodiments of a firearm (e.g., 10), buffer system, or method, for instance, the second buffer spring (e.g., 22) acts to absorb recoil energy produced by the firearm (e.g., 10). As used herein, a spring (e.g., 22) acting to reduce a peak recoil force of a firearm (e.g., 10) means that the spring (e.g., 22) reduces the peak recoil force in comparison with an otherwise equivalent firearm that does not have the spring. In addition, as used herein, a spring (e.g., 22) acting to absorb recoil energy from a firearm (e.g., 10) means that the spring (e.g., 22) stores some of the recoil energy of the firearm, for example, which energy may then be released from the spring, for instance, before the firearm is discharged again.

In some embodiments, one buffer spring absorbs recoil energy which is then transferred between the two springs, for instance, through oscillation. In particular embodiments, some or all of this recoil energy is dissipated through viscous or dry friction or both. In certain embodiments, the second buffer spring (e.g., 22) acts to absorb recoil energy produced by the firearm (e.g., 10) not otherwise absorbed by the first buffer spring (e.g., 21). Further, in particular embodiments, more of the recoil energy is absorbed by the firearm (e.g., 10), for instance, rather than by the operator, for example, in comparison with the firearm (i.e., the same firearm) except without the second buffer spring (e.g., 22).

In a number of embodiments, the firearm (e.g., 10) is a rifle. In particular embodiments, for example, the firearm (e.g., 10) is an assault rifle, such as an AR-15 or an M-16. In some embodiments, the firearm (e.g., 10) can be a semi-automatic firearm (e.g., 10) or a fully automatic firearm (e.g., 10), as examples. Further, in particular embodiments, the firearm is a rifle configured to selectably (e.g., via operation of a selector lever) fire in a fully-automatic mode and in a semi-automatic mode. Other embodiments, however, may differ. For instance, in particular embodiments the firearm can be a pistol.

Further, as mentioned above, other patent applications are incorporated herein by reference. If there are any conflicts or inconsistencies between this patent application and the patent applications to which priority is claimed, however, this patent application shall govern herein. Still further, certain embodiments include combinations of features described herein and in one or more of these different patent applications. All conceivable and feasible combinations of such features are contemplated herein including all conceivable and feasible combinations of the subject matter described herein and described in these different patent applications. For example, other embodiments contemplated include each of the embodiments described herein further including one or more of the embodiments claimed or described in each of these different patent applications.

Moreover, in the embodiment illustrated, firearm 10 and buffer system 20 include carrier spindle 25 and spindle spring 24. Other embodiments may omit such components, may include a carrier saddle (e.g., as described in the non-provisional patent application incorporated by reference herein), or both. Some embodiments, however, omit the carrier spindle (e.g., 25), spindle spring (e.g., 24), and carrier saddle, as examples. Further, some embodiments may omit the buffer weight (e.g., 23). Still further, some embodiments include only one buffer spring or at least one buffer spring, while other embodiments include 2, 3, 4, 5, or 6 buffer springs, as other examples. Moreover, some embodiments include a bolt assembly but do not include a distinct carrier assembly, while other embodiments include a bolt assembly and a distinct carrier assembly.

Further, various embodiments of the subject matter described herein include various combinations of the acts, structure, components, and features described herein, shown in the drawings, described in documents that are incorporated by reference herein, or that are known in the art. Moreover, certain procedures can include acts such as manufacturing, obtaining, or providing components that perform functions described herein or in the documents that are incorporated by reference. The subject matter described herein also includes various means for accomplishing the various functions or acts described herein, in the documents that are incorporated by reference, or that are apparent from the structure and acts described. Each function described herein is also contemplated as a means for accomplishing that function, or where appropriate, as a step for accomplishing that function.

Further, as used herein, the word “or”, except where indicated otherwise, does not imply that the alternatives listed are mutually exclusive. Even further, where alternatives are listed herein, it should be understood that in some embodiments, fewer alternatives may be available, or in particular embodiments, just one alternative may be available, as examples. 

What is claimed is:
 1. A firearm comprising: a bolt assembly; a first buffer spring aft of the bolt assembly; and a second buffer spring between the bolt assembly and the first buffer spring.
 2. The firearm of claim 1 further comprising a buffer adjusting nut that adjusts preload of the second buffer spring.
 3. The firearm of claim 2 wherein the first buffer spring is longer than the second buffer spring.
 4. The firearm of claim 2 wherein the buffer adjusting nut is aft of the second buffer spring.
 5. The firearm of claim 4 wherein the first buffer spring and the second buffer spring have a common axis.
 6. The firearm of claim 1 further comprising a buffer weight located between the first buffer spring and the second buffer spring.
 7. The firearm of claim 1 wherein the second buffer spring acts to reduce peak recoil force produced by the firearm.
 8. The firearm of claim 1 wherein the second buffer spring acts to absorb recoil energy produced by the firearm.
 9. A firearm comprising: a bolt assembly; a carrier assembly; a first buffer spring aft of the carrier assembly; and a second buffer spring between the bolt assembly and the carrier assembly.
 10. The firearm of claim 9 further comprising a buffer adjusting nut.
 11. The firearm of claim 10 wherein the buffer adjusting nut adjusts preload of the second buffer spring.
 12. The firearm of claim 10 wherein the buffer adjusting nut contacts the second buffer spring.
 13. The firearm of claim 10 wherein the buffer adjusting nut is aft of the second buffer spring.
 14. The firearm of claim 9 further comprising a buffer weight located between the first buffer spring and the carrier assembly.
 15. The firearm of claim 9 wherein the first buffer spring is longer than the second buffer spring.
 16. The firearm of claim 9 wherein the first buffer spring and the second buffer spring have a common axis.
 17. The firearm of claim 9 wherein the second buffer spring acts to reduce peak recoil force produced by the firearm.
 18. The firearm of claim 9 wherein the second buffer spring acts to absorb recoil energy produced by the firearm.
 19. A buffer system for a firearm, the firearm comprising a bolt assembly and a carrier assembly, the buffer system comprising a buffer spring and a buffer adjusting nut, wherein the buffer adjusting nut adjusts preload of the buffer spring.
 20. The buffer system of claim 19 further comprising a buffer weight and wherein the buffer adjusting nut contacts the buffer spring. 